Logging sub



2 Sheets-Sheet l R. F. MONTGOMERY ET AL LOGGING SUB Dec. 13, 1955 FiledSept. 27, 1954 l ab@ Dec. 13, 1955 Q F, MONTGOMERY ET A1. 2,726,848

LOGGING SUB 2 Sheets-Sheet Filed Sept. 27, 1954 tannini/.M3332 tion.section 13 and the mandrel section 16, respectively, are

United States Patent O LoGGlNG SUB Richard F. Montgomery, Midland, andNicolaas L. Koot, Odessa, Tex., and Marion A. Garrison, South Pasadena,Calif., said Garrison assignor to said Montgomery and said KootApplication September 27, 1954, Serial No. 458,413

19 Claims. (Cl. 255-28) 'This invention relates to a novel sub structurefor use 'in a drill string and more particularly to a telescoping subadapted to cooperate with a well caliper, such as that disclosed in acopending application to Richard F. .Montgomery and Nicolaas L. H. Koot,entitled Caliper- "ing Method and Apparatus," Serial No. 331,916, filedJanuary 19, 1953.

lt is the principal object of this invention to provide :a telescopicsub for use in a drill string, wherein said :sub may be latched incollapsed relation to transmit torque to a bit, and wherein said latchmay be released to per- 4mit extension thereof to uncover suitableopenings through which caliper `arms may be extended to caliper `thewell bore diameter as Vthe drill string is withdrawn therefrom.

A further object of this invention is to provide a sub :as set forth inthe preceding object wherein said sub may be relatched if the latchshould be inadvertently ytripped or if it is desired to' remove theVealipering tool and resume drilling.

The preferred form of our invention is described in the followingdetailed specification and illustrated by way of example in theaccompanying drawings wherein:

Fig. l is a longitudinal sectional view of a sub embodying theprinciples of our invention.

Fig. 2 is a partial longitudinal section of enlarged scale similar tothat shown in Fig. 1, and illustrates the details of the latch assemblyportion thereof with the latch in locked relation.

Fig. 3 is a similar view to Fig. 2 and shows the logging tool seated inthe sub with the latch released and the sub partially extended.

Fig. 4 is a similar view to Fig. l and shows the logging tool in placeand the sub fully extended.

Fig. 5 is a sectional View taken on line 5 5 of Fig.3.

Fig. 6 is a sectional view taken on line 6-6 of Fig. 3.

Referring now to the drawings, wherein similar reference numerals areused to designate similar parts throughout the various views shown, thelogging sub comprises two telescoping parts, an outer housing generallyindicated at 10, and an inner tubular mandrel generally indicated at 11.

The outer housing is composed of two sections 12 and 13 threadedlyconnected to each other. Similarly, the mandrel is composed of threesections 14, 15 and 16 threadedly connected together. As best seen inFig. 3, the lower end of the housing section 13 is formed with dependinglugs 17 which intermesh with corresponding recesses 18 formed in thelower section 16 of the mandrel 11, to prevent relative rotation betweenthe members lo and 11 when said members are in collapsed rela- Themeeting surfaces 48 and 49 of the housing tapered upwardly and inwardly,and the lower inner corner of the lugs 17 are chamfered, as shown at S0,for purposes which will be described presently. Two O-ring seals 19 and20 are mounted one above the other in suitable grooves provided in theexterior surface of 2,726,848 Patented Dec. 13, 1955 ICC the mandrelsection 16, and are adapted to sealingly e'ngage the' inner surface ofthe housing section 13 to provide a seal between the mandrel 11 andhousing 10,- when said members are in collapsed relation.

Referring now to Fig. 2, a latch mechanism normally retains the housing10 and the mandrel 11 in their collapsed relation. The latch comprises aplurality of latch fingers 21 pivotally mounted in suitablelongtiudinally extending slots 22 provided in the mandrel section 16.The latch fingers 21 are each pivotally mounted adjacent theirmid-points on pivot pins 23. Each of the latch fingers 21 has anoutwardly extending portion 24 adapted to hook over the upper end of thehousing section 13. The upper end of the mandrel section 16 iscounterbored as indicated at 25. A sleeve 26, having an outwardlyextending flange portion 27 adjacent its upper end, an annular outwardlyextending boss 28 adjacent its mid-portion and an outwardly extendingange 29 adjacent its lower end, is slidably mounted in the counterbore25, the outer diameter of the flanges 27 and 29 and the boss 28 eachbeing equal. Said outer diameter is such that these parts slide on theinner wall of the counterbored portion 25 of the mandrel section 16. Theannular boss 28 is adapted to abut the inner surfaces of the upper endsof the latch fingers 21 and maintain said fingers in latched relationwith the upper end of the housing section 13. A spring 30, confinedbetween the shoulder 31 formed by the lower end of the counterbore 25and the lower end of the sleeve 26, normally urges the sleeve upwardlyto its locking position. When in its locking position, the upper end ofthe sleeve 26 abuts the lower end of the mandrel section 15. The upperend of the sleeve 26 is provided with a downwardly and inwardly beveledseat 32, the purpose of which will be described presently.

A plurality of locking fingers 33 are each pivotally mounted on aplurality of pivot pins 34 in the slots 22 below the latch fingers 21. Aplurality of leaf springs 35 are each fastened at one of their ends tothe mandrel section 16 below one of the slots 22. The other end of eachspring 35 bears against the outer surface of the lower end of one of thelock fingers 33 and tends to rotate said lower end inwardly into theplane of movement of the flange 29 on the lower end of the sleeve 26.The outer surfaces of the upper portions of the lock fingers 33 normallybear against the inner surface of the housing section 13' and preventinward rotation of the f lower ends thereof. As best seen in Figs. 3 and4, when the mandrel 11 is extended relative to the housing 10, the lockfingers 33 are no longer confined by housing section 13 and rotate underthe influence of the leaf springs 35 so that the lower ends of the lockfingers 33 will catch on the upper surface of the lower ange 29 of thesleeve 26 to prevent the spring 30 from raising the sleeve 26 to itslatch locking position'.

A thrust bearing 46 is confined between the lower end of the mandrelsection 14 and an upwardly facing shoulder 47 formed adjacent the upperend of the mandrel section 15. As best seen in Fig. 4, the upper end ofthe housing section 13 abuts the lower surface of the thrust bearing 46when the assembly is in its extended relation.

A plurality of aligning pins 36 is mounted in the walls of the mandrelsection 16 and extends radially inward horizontal plane located belowthe rst plane.

caliper tool 38 adapted to be used with the logging sub.

The caliper tool 38 is provided with three pivotally mounted caliperarms 39 adapted to pivot outwardly through three longitudinallyextending slots 40 provided in the walls of the mandrel section 15. Inorder to maintain the slots 4t) in proper orientation with respect tothe aligning pins 36, a lock member 41 engages a suitable notch 42,formed in the upper end of the mandrel section 16, and is fastened tothe mandrel section by a plurality of cap screws 43. The caliper tool 38is provided with a downwardly facing beveled shoulder i4, which isadapted to seat on the beveled seat 32 formed on the upper end of thesleeve 26.

In the use of the sub, the parts are assembled in the positionsillustrated in Fig. l. A bit (not shown) is connected to the lower endof the mandrel section 16 in the usual manner and the upper end of thehousing section 12 is connected to the lower end of a drill stringindicated at 4S. The assembly is lowered into the well and drilling isperformed in the usual manner by rotating the drill string. The rotationof the drill `string is transmitted from the housing 1.0 to ,the mandrel11 through the interlocking lugs and recesses 17 and 18, respectively.Since the mandrel 11 and housing 10 are sealed to each other by theO-ring `seals 19 and 20, duid may be circulated downwardly therethrough,out through the bit and back up the annular space surrounding the stringin the usual manner.

When it is desired to remove the string from the Well and simultaneouslylog the well diameter, .the Vcaliper tool 38 is lowered or droppedthrough the well string. When the shoulder 44 on the caliper tool seatson the seat 32 on the upper end of the sleeve 26, continued downwardmovement of the caliper tool 38 will force vthe sleeve downwardly to theposition shown in Fig. 3, wherein the boss 28 moves out of engagementwith KVthe inner surface of the upper ends of the latch fingers `21 andthe lower surface thereof contacts lthe innersurface of the lower endsof the latchjiingers 2,1 to rotate the upper end of the latch lingersinwardly utorelease the Ymandrel 11.for .outward extension relativeto-theghousing 10. As the caliper 38 seats in thesub, the grooves 37 onthe lower end of the :caliper 38 cooperate with the Aaligning pins 36 torotate the caliper and automatically bring the caliper arms 39 intoregister-with the slots 40.

As the well string is raised, ;the housing y10 is raised therewithrelative to the mandrel 11 Auntil the upper surface of the housing 13contacts the lower surface of the thrust bearing 46. At lthis time theslots :40 are located completely below the lower end of the housing -10and the caliper arms 39 are permitted to swing outwardly into contactwith the bore wall. It will be appreciated that since the lugs 17 are nolonger in engagement with the recesses 18, the drill string mayberotated for dismembering purposes without rotating lthe mandrel 11 andthe caliper tool 38 seated therein.

If the latch fingers`21 should be trippedaccidentally, or it is desiredto remove vthe caliper and relatch the assembly to continue drilling,this may be accomplished by merely setting down Weight on the drillstring since the lock fingers 33 have been rotated by thev leaf springs35 into the position shown in Fig. 3. In this position, the lock fingers33 will hold the sleeve 26 down when the caliper 3S is removed. Uponsubsequent downward movement of the housing 10, either the chamfer 50 onthe lower ends of the lugs 17 or the upwardly and inwardly inclinedsurface 48 on the lower end of the housing will rotate the upper ends ofthelatch fingers 21 inwardly. Further downward movement of the housing10 will rotate the upper ends of the lock fingers 33 inwardly to releasethe sleeve 26 for upward movement under the influence of the spring 30,to force the upper ends of the latch fingers 21 outwardly to again hookover the upper end of the housing section 13.

From the foregoing description it may be seen that we have provided anovel telescoping sub structure which may be inserted into a drillstring immediately above a bitand which is adapted to cooperate with asuitable caliper tool for logging the well as the drill string iswithdrawn therefrom, and wherein said sub may be locked in collapsedrelation to transmit torque from said drill string to said bit, andwherein lsaid sub may be unlatched to permit extension thereof tocalipering relation.

While we have shown and described the preferred form of our invention,itis obvious that various changes may be made therein by those skilledin the art without departing from the spirit o f the invention asdefined in the appended claims.

Having thus described our invention, what we claim and desire to secureby Letters Patent is:

l. In a logging sub adapted `to be inserted in a drilling string, ahousing, a tubular mandrel telescopically rcceived in said housing,releasable latch means adapted to maintain said mandrel and housing intelescoped relation, said latch means comprising an upwardly facinginternal shoulder in said housing, a plurality of hook-shaped latchfingers pivotally mounted on said mandrel adjacent their mid-portionsand adapted lto hook over said upwardly facing shoulder, a sleeveslidably mounted for vertical movement from an upper to a lower positionwithin said mandrel, an Iexternal boss on said sleeve adapted to bearagainst the upper inner surface of said latch lingers and maintain .saidfingers in latching relation when said sleeve is in its uppermostposition and to bear against the lower inner surface of said latchfingers to rotate the latch fingers to release position when saidysleeve moves downwardly.

2. In a logging sub adapted to bc inserted in a drilling string, ahousing, a tubular mandrel telescopically received in saidhousing, apair ofO-ring seals mounted on said mandrel and vsealingly engaging thelower inner surface of said housing when `said mandrel and salti housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, Asaid-latch .means:comprisin g an upwardly facing internal `shoulder in said housing, aplurality of hook-shaped latch fingers Ipivotally mounted on saidmandrel adjacent their mid-portions and adapted to hoo?. over saidupwardly facing shoulder, a sleeve slidably mounted for .verticalmovement from an upper to a lower position within said mandrel, anexternal boss on said sleeve adapted to bear against the upper innersurface of said latch fingers and maintain said lingers in latchingrelation when `said ,sleeve is in its uppermost position and to bearagainst the lower inner surface of said latch fingers to rotate thelatch'fingers to release position when said sleeve moves downwardly.

3. In a logging sub adapted to be inserted in a drilling string, ahousing, Aa tubular mandrel telescopicalb rcceived invsaid housing, apair oflO-ring seals mounted on said mandrel rand `sealingly engagingthe lower inner surface lof said -housing .when `said mandrel and saidhousingare inv telescoped relatiolnlieleasable latch means adapted tomaintain saidmandrel and housing in telescoped relation, said latchmeans comprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch `fingers pivotally mounted on saidmandrel adjacent their Vmidi-portions and adapted to hooi: over saidupwardly -facing shoulder, a sleeve slidably mounted for verticalmovement from an upper to a lower position within said mandrel, anexternal boss on said sleeve adapted to bear against the upper innersurface of said latch fingers and maintain said `iingers in latclrrelation when said sleeve isy in 4 its uppermost posities-t andlto,bear"againsththelowcrinner surface of said latch fingerstoY rotateythe latchifingersrto release position when said sleevewrnovesdownwardly, a plurality of longitudinally extending slots in rsaidmlandrel above said latch fingers adapted tobelunoveredtopermit thepassage of logging .elements therethrough `when said mandrel and housingare in extended relation.

4. n a logging sub adapted to beinserted' in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealinglyl engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveisin its uppermost position and to bear against the lower inner surfaceof said latch fingersto rotate the latch fingers to release positionwhen said sleeve moves downwardly, a plurality of longitudinallyextending slots in'said mandrel above said latch fingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, and a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, one of said pins at one horizontal plane and two pins in alower plane one directly below said one pin and the other spacedcircumferentially 120 therefrom, said pins being adapted to cooperatewith a suitably shaped groove on a logging tool to align the loggingelements thereof with said slots.

5. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and to hear against the lower inner surfaceof said latch fingers to rotate the latch fingers to release positionwhen said sleeve moves downwardly, a downwardly and inwardly taperedseat on the upper end of said sleeve adapted to receive a logging tooldropped through the drilling string, a plurality of longitudinallyextending slots in said mandrel above said latch fingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, and a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, one of said pins at one horizontal plane and two pins in alower plane one directly below said one pin and the other spacedcircumferentially 120 therefrom, said pins being adapted to cooperatewith a suitably shaped groove on said logging tool to align the loggingelements thereof with said slots.

6. in a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted4 on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, Vaplurality of hook-shaped latch fingers pivotally mounted on said maniadapted to bear against the upper inner surface of said latch fingersand maintain said fingers in latching relation when said sleeve is inits uppermost position and to bear against the lower inner surface ofsaid latch fingers to rotate the latch fingers to release position whensaid sleeve moves downwardly, a downwardly and inwardly tapered seat onthe upper end of said sleeve adapted to receive a calipering tooldropped through the drilling string, a plurality of longitudinallyextending slots in said mandrel above said latch fingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, one of said pins at one horizontal plane and two pins in alower plane one directly below said one pin and the other spacedcircumferentially therefrom, said pins being adapted to cooperate with asuitably shaped groove on a logging tool to align the logging elementsthereof with said slots, and means on the lower end of said housingadapted to interengage with means on said mandrel when said mandrel andhousing are in telescoped relation to prevent relative rotationtherebetween.

7. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means; adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardlyY facing internal shoulder in said housing, aplurality of' hook-Shaped latch fingers pivotally mounted on said man-4drel adjacent their mid-portions and adapted to hook over` said upwardlyfacing shoulder, a sleeve slidably mountedl for vertical movement froman upper to a lower position within said mandrel, an external boss onsaid sleeveadapted to bear against the upper inner surface of saidllatch fingers and maintain said fingers in latching relation when saidsleeve is in its uppermost position and to bear` against the lower innersurface of said latch fingers to rotate the latch fingers to releaseposition when said sleevel moves downwardly, a downwardly and inwardlytapered seat on the upper end of said sleeve adapted to receive acalipering tool dropped through the drilling string, a plu-- rality oflongitudinally extending slots in said mandrel above said latch fingersadapted to be uncovered to permit' the passage of logging elementstherethrough when said mandrel and housing are in extended relation, aplurality of radially inwardly extending aligning pins in the lower'portion of said mandrel, one of said pins at one hori Zontal plane andtwo pins in a lower plane one directly below said one pin and the otherspaced circumferentially 120 therefrom, said pins being adapted tocooperatei with a suitably shaped groove on a logging tool to align thelogging elements thereof with said slots, means on` the lower end ofsaid housing adapted to interengagel with means on said mandrel whensaid mandrel and boils-- ing are in telescoped relation to preventrelative rotation` therebetween, a downwardly facing thrust bearing:

' mounted on said mandrel adjacent the upper end thereof',

said thrust bearing being adapted to abut said upwardlyY facing shoulderin said housing when said mandrel and' housing are in extended relation.

8. In a logging sub adapted to be inserted in a drillingn string, ahousing, a tubular mandrel telescopically re ceived in said housing,releasable latch means adapted tomaintain said mandrel and housing intelescoped relation,

said latch means comprising an upwardly facing internal, shoulder insaidhousing, a plurality of hook-shaped latch fingers pivotally mounted onsaid mandrel adjacent their` mid-portions and adaptedrto hookover saidupwardly facing shoulder; a sleeve slidably mounted for.verticalmovement frornan upper to a lower position within said,

housing to move downwardly past said latch fingers, saidv lcclt fingersbeingadapted to be contacted by the lower end of said housing androtated thereby to release said sleeve for upward movement to relatchsaid latch fingers, and means normally urging said sleeve toward itsuppermost position.

9. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in tele-V scoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hooleshaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and to bear against the lower inner surfaceof said latch fingers t0 rotate the latch fingers to release positionwhen said sleeve moves downwardly, releasable lock fingers pivotallymounted on said mandrel below said latch fingers, said lock fingersbeing adapted to hold said sleeve in its lowermost position to permitsaid housing to move downwardly past said latch fingers, said lockfingers being adapted to be contacted by the lower end of said housingand rotated thereby to release said sleeve for upward movement t0relatch said latch fingers, and means normally urging said sleeve towardits uppermost position.

l0. ln a logging sub adapted to be inserted in a drilling string.housing, a tubular mandrel telescopically received in said housing, apair of 0-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing `when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hookshaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and Vto bear against the lower innersurface of said latch fingers to rotate the latch fingers to releaseposition when said sleeve moves downwardly, releasable lock fingerspivotally mounted on said mandrel below said latch fingers, said lockfingers being adapted to hold said sleeve in its lowermost position topermit said housing to move downwardly past said latch lingers, saidlock fingers being adapted to be contacted by the lower end of saidhousing and rotated thereby to release said sleeve for upward` movementto relatch said latch fingers, means normally urging said sleeve towardits uppermost position, and a plurality of longitudinally extendingslots in said mandrel 8 above Said .lath;nsereadapted, mbe. uncovered,t0 permit the passageof1loggingelernents tlierethrr'iughV when saidmandrel anclhousing are nextendedrelation 1l in ,aloggingsubadaptedtobefinserted in a drilling string, a,hou sing, a, tub u la rmandrel telescopicallyreceived -facing shoulder, a sleeve slidablymounted for vertical movement 'from ,an, upper Yto a lower positionwithin said mandrel, an external b oss ,on .said sleeve adapted to bearagainst the upper inner` surface of said latch fingers and maintainsaidV fingers inlatehingrelation when said sleeve is Vin its uppermostpositionand to bear against the lower innersurface `of said latchfingers to rotate the latch fingers to releaseposition when said sleevemoves downwardly, releasable loclcfingers pivotally mounted on saidmandrel belowlsaid latch fingers, saidV lock fingers being adaptedtohold said .sleevein itsiowermost position to permit `said',housing,to`move,downwardly past said latch fingers,lsaid' loclpfingers beingadapted to be contacted by the lower end of -said housing and rotatedthereby to release said sleevey for upward movement to relatch saidlatchfingers, means norrnally urging said sleeve toward its uppermostposition, a plurality of longitudinally extending slots in said mandrelabovesaid latch ngers adapted to be uncovered to permit the passage oflogging elements .therethrough when said mandrel and housing lare inextendedy relation, and a plurality of radially inwardly/ extendingaligning pins in the lower portion of said mandrel, one rof said pins atone horizontal plane and twopins inla lower plane ,one directly belowsaid one pin and theotherspacedvcircurnferentially 1243* therefrom. saidpins being kadapted v to cooperate with a suitably shaped groove onalogging tool to align the logging elements thereofwith-said slots.

l2.` ln a logging sub adapted tobe inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing,apair of O- ring seals mounted on said mandrel and sealinglyengaging thelower inner :surface ofsaidhousing when saidmandrel and said housing arcinv telescoped relation, releasable latch means adapted to maintainsaidmandrel and housing in telescoped relation,

-said latch means comprising an upwardly facing internal shoulder insaid housing, a plurality of hook-shaped latch fingers pivotallymountedonsaid mandrel adjacent their mid-portions and adaptedto hookover said upwardly facing shoulder,.a`fsleeve slidably mounted forvertical lmovement from an upper to a lower position within saidmandrel, an external boss on said sleeve adapted to bear againsttheupper inner surface of said latch fingers and maintain said fingers inlatching relation when said sleeve is'in its uppermost lposition and tobear against the lower inner surfaceof said -latch fingers to rotate thelatch fingers to release position when said sleeve moves downwardly,releasable lock4 fingers pivotally mounted on said mandrel belowsaidlatchfingers, said lock fingers being adapted toholdsaid sleeve in itslowermost position to permit said housing to move downwardly past saidlatch fingers, said lovckfingers being adapted to be contactedbyithedower end of said housing and rotated thereby to release saidsleeve, for upward movement to relatch said latch fingers,.meansnorrnally urging said sleeve toward itsupperrnostposition,downwardly and inwardly tapered seat on the, upp e r. end of said sleeveadapted to receive a logging ltool dropped throughA the drilling string,a plurality of. longitudinally extending slots in said mandrel abovesaidlatch finger-s adapted to be uncovered to permit the ,passageof,logging, elements therethrough 4when said 9 Y mandrel and housingare in extended relation, and a plurality of radially inwardly extendingaligning pins in the lower portion of said mandrel, one of said pins atone horizontal plane and two pins in a lower plane one directly belowsaid one pin and the other spaced circumferentially 120 therefrom, saidpins being adapted to cooperate with a suitably shaped groove on saidlogging tool to align the logging elements thereof with said slots.

13. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidablyk mounted for vertical movement froman upper to a lower position Within said mandrel, an external boss onsaid sleeve adapted to bear against the upper inner surface of saidlatch fingers and maintain said fingers in latching relationrwhen saidsleeve is in its uppermost position and to bear against the lower innersurface of said latch ngers to rotate the latch fingers to releaseposition when said sleeve moves downwardly, releasable lock fingerspivotally mounted on said mandrel below said latch lingers, said lockngers being adapted to hold said sleeve in its lowermost position topermit said housing to move downwardly past said latch fingers, saidlock fingers being adapted to be contacted by the lower end of saidhousing and rotated thereby to release said sleeve for upward movementto relatch said latch lingers, means normally urging said sleeve towardits uppermost position, a downwardly and inwardly tapered seat on theupper end of said sleeve adapted to receive a ylogging tool droppedthrough the drilling string, a plurality of longitudinally extendingslots in said mandrel above said latch fingers adapted to be uncoveredto permit the passage of logging elements therethrough when said mandreland housing are in extended relation, a plurality of radially inwardlyextending aligning pins inthe lower portion of said mandrel, one of saidpins at one horizontal plane and two pins in a lower plane one directlybelow said one pin and the other spaced circumferentially 120 therefrom,said pins being adapted to cooperate with a suitably shaped groove onsaid logging tool to align the logging elements thereof with said slots,and means on the lower end of said housing adapted to interengage withmeans on said mandrel when said mandrel and housing are in telescopedrelation to prevent relative rotation therebetween.

l14. Inv av logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, vaplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and to bear against the lower inner surfaceof said latch fingers to rotate the latch fingers to release positionwhen said sleeve moves downwardly, releasable lock fingers pivotallymounted on said mandrel below f Y .'10 i I said latch nger's, said lockfingers being adapted to hold said sleeve in its lowermost position topermit said housing to move downwardly past said latch fingers, Vsaidlock fingers being adapted to be contacted by the lower end of saidhousing and rotated thereby to release said sleeve for upward movementto relatch said latch fingers, means normally urging said sleeve towardits uppermost position, a downwardly and inwardly tapered seat on theupper end of said sleeve adapted to receive a logging tool droppedthrough the drilling string, a plurality of longitudinally extendingslots in said mandrel above said latch fingers adapted to be uncoveredto permit the passage of logging elementsy therethrough when saidmandrel and housing are in extended relation, a plurality of radiallyinwardly extending aligning pins in the lower portion of said mandrel,one of said pins at one horizontal plane and two pins in a lower planeone directly below said one pin and the other spaced circumferentiallytherefrom, said pins being adapted to cooperate with a suitably shapedgroove on said logging tool to align the logging elements thereof withsaid slots, means on'the lower end of said housing adapted tointerengage with means on said mandrel when said mandrel and housing arein telescoped relation to prevent relative rotation therebetween, adownwardly facing thrust bearing mounted on said mandrel adjacent theupper end thereof, said thrust bearing being adapted to abut saidupwardly facing shoulder in said housing when said mandrel and housingare in extended relation.

l5. ln a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and to bear against the lower inner surfaceof said latch fingers to rotate the latch fingers to release positionwhen said sleeve moves downwardly, a plurality of longitudinallyextending slots in said mandrel above said latch fingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, and a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, said pins being adapted to cooperate with a suitably shapedgroove on a logging tool to align the logging elementsthereof with saidslots.

16. ln a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch fingers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear again-st the upper inner surface of said latchfingers and maintain said fingers in latching relation when said sleeveis in its uppermost position and to bear against the lower inner surfaceof said latch fingers torotate the latch fingers to release positionwhen sa'i'dsleeve moves'downwardly, a downwardly and inwardly"tapered4seat on the'upper end of said sleeve adapted to receivela logging tooldropped through the drilling string, a Vplurality of longitudinallyextending slots in said mandrel above said latch fingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, and a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, said pins being adapted to cooperate with a suitably shapedgroove on said logging tool to align the logging elements thereof withsaid slots.

17. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upwardly facing internal shoulder in said housing, aplurality of hook-shaped latch ngers pivotally mounted on said mandreladjacent their mid-portions and adapted to hook over said upwardlyfacing shoulder, a sleeve slidably mounted for vertical movement from anupper to a lower position within said mandrel, an external boss on saidsleeve adapted to bear against the upper inner surface of said latchlingers and maintain said lingers in latching relation when said sleeveis in its uppermost position and to bear against the lower inner surfaceof said latch lingers to rotate the latch fingers to release positionwhen said sleeve moves downwardly, a plurality of longitudinallyextending slots in said mandrel above said latch lingers adapted to beuncovered to permit the passage of logging elements therethrough whensaid mandrel and housing are in extended relation, and a plurality ofradially inwardly extending aligning pins in the lower portion of saidmandrel, one of said pins at one horizontal plane and two pins in alower plane one directly below said one pin and the other spacedcircumferentially 120 therefrom, -said pins being adapted to cooperatewith a suitably shaped groove on a logging tool to align the loggingelements thereof with said slots, interengaging means on said mandreland housing adapted to prevent relative rotation therebetween when saidmandrel and housing are in telescoped relation, and a downwardly facingthrust bearing adjacent the upper end of said mandrel adapted to abutthe upwardly facing shoulder in said housing when said mandrel andhousing are in extended relation.

18. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing, apair of O-ring seals mounted on said mandrel and sealingly engaging thelower inner surface of said housing when said mandrel and said housingare in telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation, said latch meanscomprising an upward-,

ly facing internal shoulder in said housing, aplurality ofhook-shapedlatch fingers pivotally-mounted Von said mandrel adjacenttheir mid-portions and adapted to hook over said upwardly facingshoulder, a sleeve slidably mounted for vertical movement from an upperto a lower position within said mandrel, an external boss on said sleeveadapted to bear against the upper inner surface of said latch fingersand maintain said fingers in latching relation when said sleeve is inits uppermost position and to 'near against the lower inner surface ofsaid latch fingers to rotate the latch lingers to release position whensaid sleeve moves downwardly, a downwardly and inwardly tapered seat onthe upper end of said sleeve adapted to receive a logging tool droppedthrough the drilling string, a plurality of longitudinally extendingslots in said mandrel above said latch fingers adapted to be uncoveredto permit the passage of logging elements therethrough when said mandreland housing are in extended relation, and a plurality of radiallyinwardly extending aligning pins in the lower portion of said mandrel,one of said pins at one horizontal plane and two pins in a lower planeone directly below said one pinand the other spaced circumferentiallytherefrom, said pins being adapted to cooperate with a suitably shapedgroovev on said logging tool to align the logging elements thereof withsaid slots, interengaging means on said mandrel and housing adapted toprevent relative rotation therebetween when said mandrel and housing arein telescoped relation, and a downwardly facing thrust bearing adjacentthe upper end of said mandrel adapted to abut the upwardly facingshoulder in said housing when said mandrel and housing are in extendedrelation.

i9. In a logging sub adapted to be inserted in a drilling string, ahousing, a tubular mandrel telescopically received in said housing,releasable latch means adapted to maintain said mandrel and housing intelescoped relation, said latch means comprising an upwardly facinginternal shoulder in said housing, a plurality of latch fingerspivotally mounted on said mandrel adjacent their mid-portions andadapted at their upper ends to engage said upwardly facing shoulder inlatching relation, a sleeve slidably mountedfor vertical movement froman upper to a lower position within said mandrel, and external means onsaid sleeve adapted to bear against the upper end portion of said latchfingers and maintain said lingers in latching relation with saidshoulder when said sleeve is in its uppermost position and to engage thelower end portion of said latch lingers to pivot said fingers to releaseposition when said sleeve moves downwardly. i

References Cited in the file of this patent UNITED STATES PATENTS1,599,998 Heck Sept. 14, 1926 2,102,080 Kinley Dec. 12, 1937 2,468,849Trainor May 3, 1949 2,621,745 Toelke Dec. 16, 1952-

